The present invention relates to a variable valve timing control apparatus for an internal combustion engine which includes both of an operation angle control mechanism capable of varying an operation angle of an intake valve (hereinafter referred to as intake operation angle) and a phase control mechanism capable of varying a maximum lift phase of an intake valve (hereinafter referred to as intake maximum lift phase). The present invention further relates to a method of controlling a variable valve timing of an internal combustion engine.
For the purpose of improving the output and the fuel consumption of an internal combustion engine and reducing the exhaust emission, various variable valve timing control apparatuses for varying the opening and closing characteristics (valve lift characteristics) of intake and exhaust valves have heretofore been proposed. For example, a variable valve timing control apparatus that includes a valve lift control mechanism capable of varying a valve lift and an operation angle of an intake valve in two stages and a phase control mechanism capable of varying a maximum lift phase of an intake valve continuously are used jointly is disclosed in Japanese Patent Provisional Publication No. 2000-18056.